I need to contact my guests after they have departed but am unsure whether the messaging through AirBnb continues. Am I able to obtain from AirBnb the guests e-mail so that I can be sure he receives my message. The reason to reach out to him is to obatin his Bank details so that I can process a refund to him of money paid to me for items during his stay.
Yes, guests will still receive messages via the Airbnb system. Also, never send the guest money outside of Airbnb. The proper way to issue a refund is through the Resolution Center: airbnb.fr/resolutions.